title: Assessing the fertility potential of equine semen samples using the reducible dyes methylene green and resazurin.
abstract: The objective of this study was to determine if spermatozoal reduction of the dyes methylene green to colorless and resazurin to pink or colorless was associated with the fertility potential of an equine semen sample. Fifty samples from 38 stallions were evaluated for the number of spermatozoa per milliliter and number of motile sperm per milliliter. Methylene green (20 micrograms/mL of semen) or resazurin (85 micrograms/mL of semen) was added to 3-mL aliquots of semen. Semen samples were identified as having low fertility potential (< 200 x 10(6) total cells/mL and < 140 x 10(6) motile cells/mL) or high fertility potential (> or = 200 x 10(6) total cells/mL and > or = 140 x 10(6) motile cells/mL). The sensitivities were 80% for the methylene green, 68% for the resazurin to pink, and 60% for the resazurin to colorless tests. The specificities were 80% for the methylene green, 79% for the resazurin to pink, and 92% for the resazurin to colorless tests. The overall accuracies were 80% for the methylene green test, 74% for the resazurin to pink test, and 76% for the resazurin to colorless tests. The methylene green and resazurin reduction tests can provide valuable information on the fertility potential of an equine semen sample.
authors.affiliation: Division of Range Animal Science, Sul Ross State University, Alpine, Texas 79832, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: Carter
authors.forename: S A
authors.initials: SA
authors.lastname: Ericsson
authors.forename: C D
authors.initials: CD
authors.lastname: Corn
authors.forename: P R
authors.initials: PR
authors.lastname: Weyerts
authors.forename: M G
authors.initials: MG
authors.lastname: Dart
authors.forename: S G
authors.initials: SG
authors.lastname: Escue
authors.forename: J
authors.initials: J
authors.lastname: Mesta
mesh_terms: D000818:Animals; D003116:Color; D004396:Coloring Agents; D005298:Fertility / Q000502:physiology*; D006736:Horses; D066298:In Vitro Techniques; D007202:Indicators and Reagents; D008297:Male; D008751:Methylene Blue / Q000031:analogs & derivatives; D010078:Oxazines; D010084:Oxidation-Reduction; D011237:Predictive Value of Tests; D012661:Semen / Q000502:physiology*; D014966:Xanthenes
chemical_list: D004396:Coloring Agents; D007202:Indicators and Reagents; D010078:Oxazines; D014966:Xanthenes; C005843:resazurin; C028673:methylene green; D008751:Methylene Blue